This is a list of error codes returned by the Kernal's disk routines:

$00	Drive(r) error, value in B
$01	Volume Full
$02	File Not Found
$03	Dir Full
$04	Not A Dir
$05	Dir Is Not Empty
$06	Not A File
$07	File Length Is Zero
$08	Address out of range
$09	File Name Already Exists
$0a	Already at root
$0b	Dir not found
$0e	Invalid Volume
$13	not FAT16
$15	file name too long
$1b	requested bytes beyond end of file
$22	Device not present
$23	Dir not found
$2e	No MBR